ISO 11973:2015

INTERNATIONAL ISO
STANDARD 11973
Second edition
2015-09-15
Heat-resistant cast steels and alloys
for general applications
Aciers et alliages moulés réfractaires destinés à des applications
générales
Reference number
©
ISO 2015
© ISO 2015, Published in Switzerland
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ii © ISO 2015 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 General conditions for delivery . 1
4 Heat treatment . 1
5 Chemical composition . 1
6 Mechanical properties . 1
7 Maximum use temperature . 1
8 Supplementary requirements . 1
Annex A (informative) UNS cast grades similar to ISO cast grades . 5
Bibliography . 6
Foreword
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The committee responsible for this document is ISO/TC17, Steel, Subcommitee SC11, Steel castings.
This second edition cancels and replaces the first edition (ISO 11973:1999), which has been technically
revised with the following changes:
— Clause 8 revised;
— Table 1 composition limits modified — various grades;
— Tables 1 and 2 — grade number added;
— Annex A added.
iv © ISO 2015 – All rights reserved

INTERNATIONAL STANDARD ISO 11973:2015(E)
Heat-resistant cast steels and alloys for general applications
1 Scope
This International Standard specifies chemical composition and mechanical properties of cast steels
and alloys for heat-resistant service.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 4990, Steel castings — General technical delivery requirements
3 General conditions for delivery
Materials furnished in conformity with this International Standard shall conform to the applicable
requirements of ISO 4990 including the supplementary requirements that are indicated on the enquiry
and purchase order.
4 Heat treatment
GX40CrSi13, GX40CrSi17, GX30CrSi7, GX40CrSi24, GX40CrSi28, and GX130CrSi29 may be annealed at a
temperature of 800 °C to 850 °C. If required, GX30CrSi7 may also be supplied in the as-cast condition.
Other grades produced according to this International Standard do not require heat treatment. If heat
treatment is required, the treatment should be established by agreement between the manufacturer
and the purchaser, and shou
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